This document provides information about a hot air oven and its uses. It discusses how hot air ovens work by providing temperatures higher than the atmosphere, typically between 50-250°C, and are used for rapid drying and sterilization. It also details how a hot air oven is used for the standard method of determining seed moisture content by precisely heating samples to eliminate water. Specifications are given for common crops dried in hot air ovens, including temperatures and drying times.

1. WELCOME
HOT AIR OVEN
PRESENTED BY
KIRAN DASANAL
(PALB7319)

2. INTRODUCTION
• An oven provides a temperature higher than that of
atmosphere.
• The temperature range covered by ovens is between
50-250°C.
• These are used for rapid evaporation of materials,
rapid drying and for sterilization of articles that can
be sterilized by dry heat.

3. CONT…
• The standard method for determining moisture
in seed is the hot air oven method.
• the principle of this method is the elimination
of water from the seed by heating under
precisely controlled condition.

4. HOT AIR OVEN

5. CONT….
• We offer double walled thermostatically controlled
hot air oven.
• The inner chamber of this hot air oven are made of
alluminium/stainless steel. Outer body is made of
mild steel.
• Beaded heating Elements are placed under the ribs at
the bottom and sides. these are also availble with
special arrangement for digital temperature
conteoller, alarm system, timer, blower etc.

6. Placing the seed sample in oven for
seed moisture determination

7. Removing the seed samples from oven

8. USE THE RESULTS OF THE WEIGHING TO CALCULATE
MOISTURE CONTENT
•
 Moisture content is calculated on a wet weight
basis and expressed to one decimal place.
 Replicates should not differ by more than 0.2%.
 For samples tested without pre-drying use the
following formula:
%Moisture content=weight of fresh seeds-weight of dry seeds×100
weight of fresh seeds

9. Common
Name
Scientific Name
Drying
temperature
(ºC)
Drying
time (hr)
Grinding
CEREALS
Paddy Oryza sativa 130 2 Fine
Wheat Triticum spp. 130 2 Fine
Barley Hardeum spp. 130 2 Fine
Maize Zea mays 130 4 Fine
Sorghum Sorghum bicolor 130 2 Fine
Pearl millet Pennisaetum typhoides 130 1 Fine
Pulses
Black gram Vigna mungo 130 1 Coarse
Cow pea V. sinensis 130 1 Coarse
Green gram V. radiate 130 1 Coarse
Pegeon pea Cajanus cajan 130 1 Coarse
Soybean Glycine max 103 17 Coarse
French bean Phaseolus vulgaris 130 1 Coarse
Chick pea Cicer arietinum 130 1 Coarse
Mustard Brassica spp. 130 2 Fine
Oil seeds
Safflower Carthomus tinctorius 103 17 No
Castor Ricinus communis 103 17 Coarse
Ground nut Arachis hypogea 103 17 Coarse
Sunflower Helianthus annus 103 17 No
Onion Allium cepa 103 17 No
Specification of drying duration and temperature for seed moisture test (ISAT)

10. Fiber crops
Cotton Gossypium spp. 103 17 Fine
Vegetables
Cucumber Cucumis sativus 130 1 Fine
Pumpkin Cucurbita moschata 130 1 Fine
Cabbage B olaracea var. capitata 103 17 No
Cauliflower B. olaracea var. botrytis 103 17 No
Tomato Lycopersicon esculentum 130 1 No
Brinjal Solanum melongena 103 17 No
Okra Abelmoscus esculentus 1 130 Coarse
Carrot Daucus carota 130 1 No
Raddish Raphanus sativus 103 17 No
Beet Beta vulgaris 130 1 Coarse

11. THANK YOU